The invention relates to a continuous laundry machine, more particularly for laundering batches consisting of unbundled items, the machine having a washing drum which is disposed in a casing at a distance from the casing inner wall and which is rotatable around its longitudinal axis and whose generated surface is formed with apertures for the passage of washing liquid and through which the laundry can be moved axially, in countercurrent to the washing liquid, by means of a convey or disposed inside the drum, the gap between the same and the casing being radially subdivided into outer pockets or chambers or the like to and from which washing liquid can be supplied and removed, possibly via pipes, such pockets or chambers or the like being disposed substantially symmetrically of an inner washing chamber or pocket of the radially subdivided drum.
The earliest models of machines of this kind had a horizontally inclined drum dipping into an open trough-like casing containing liquid at a constant level. Machines of this kind cannot provide different treatment zones each with its own washing conditions.
The casing therefore became drum-shaped and the gap between the casing and the drum was subdivided by annular ribs terminating at a distance from the drum, as disclosed for example by German Auslegeschrift No. 1,303,233. In this known washing machine the drum interior is also subdivided by annular ribs. Laundry is conveyed through the drum by means of conveying or entraining ribs and by means of a trough which has provision for limited axial movement. This known machine cannot provide complete separation between adjacent washing areas either.
To reduce this disadvantage the volume of the gap between the drum and the casing is reduced so that the most of the washing liquid is received by the drum. The result is still unsatisfactory, since optimum operation of a machine of this kind requires very precise separation and isolation between the discrete washing zones -- e.g. for cold prewash, hot prewash, boiling, hot rinse and cold rinse, so far as conditions such as temperature, addition of detergent and other additives are concerned.
Nor can these requirements be met by the washing machine disclosed by German Offenlegungsschrift 1,964,414. In this machine, comprising a closed drum without a casing, not only the discrete batches of laundry but also the discrete washing baths can be separated from one another; clearly, however, there cannot be separate control of the discrete baths and an appropriate supervision of temperature, detergent concentration, additive concentration etc. conditions.
A considerable disadvantage of the machines hereinbefore described is that they cannot be enlarged or reduced by one or more washing areas as may often be desirable for a variety of reasons.
If it is required to have this facility for amplifying the machine and to be able to have accurate separation of the items of laundry and of the baths, plus provision for reducing and maintaining particular conditions in the washing zone, the only solution of the problem is still to use a washing machine of the kind disclosed by German Patent Specification 1,130,403. The machine disclosed thereby does not have a continuous drum but a number of consecutive units completely separated from one another. The laundry is transferred from any washing unit to the washing unit which is adjacent as considered in the direction of conveyance by transfer means which take the form of scoop-like or shovel-like receptacles adapted to pivot around an axis extending transversely of the conveying direction. This machine has proved very satisfactory in practice because of the advantages just referred to, but the transfer of laundry between consecutive washing units often causes difficulties, for operating difficulties are bound to occur when moving conveyors of the kind described have to deal with an unwieldly material such as wet washing.